People who need a screening mammogram should schedule their appointment before their first dose of the COVID-19 vaccine or at least four weeks after receiving their second vaccine dose. The challenge is that swollen or enlarged lymph nodes can -- on rare occasions -- be a sign of breast cancer. However, after a vaccine, they are more likely a sign that the vaccine is helping the body develop an immune response to protect it from getting COVID-19.
Swollen Lymph Nodes Are Side Effects of Several Vaccines
Swollen lymph nodes are a sign that your body is developing an immune response to your vaccine. This can happen with many different vaccines, but it is more common after a COVID-19 vaccine. Enlarged lymph nodes were noticeable in approximately 10 percent of women in the Moderna clinical trials. According to Lars Grimm, MD, a breast radiologist at Duke Health, they are being seen more frequently by radiologists because sensitive mammography technology can detect swollen lymph nodes that can’t be felt or seen with the naked eye.
“In the past, we might see enlarged lymph nodes once every few weeks,” said Dr. Grimm, who is also a member of the Society for Breast Imaging, which recently came out with the screening recommendation. “Now with widespread vaccination efforts, we are seeing multiple cases of swollen lymph nodes every day.”
“When you get your mammogram, it’s important to tell the technologist if you received a COVID-19 vaccine, when you received it, and in which arm it was given.”
Don’t Cancel or Delay the COVID-19 Vaccine or Your Mammogram
Dr. Grimm stressed that getting the COVID-19 vaccine AND getting a screening mammogram are both important. Neither should be avoided. Rather, he said, it’s important that people take this side effect of the COVID-19 vaccine into consideration when making their appointment.
“When you get your mammogram, it’s important to tell the technologist if you received a COVID-19 vaccine, when you received it, and in which arm it was given,” Dr. Grimm said. “Usually, the lymph node swelling occurs on the side you received the vaccine.”
Getting a screening mammogram too soon after receiving a COVID-19 vaccine won’t do you any harm. “It may mean we might take a few additional pictures and recommend a short follow-up to ensure the lymph nodes return to normal size,” he said. Importantly, Duke Health will not cancel your screening mammogram appointment if you have had a recent vaccine.